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[PATCH v3 06/28] hw/xen: take iothread mutex in xen_evtchn_reset_op()

Posted by David Woodhouse 2 years, 3 months ago

From: David Woodhouse <dwmw@amazon.co.uk>

The xen_evtchn_soft_reset() function requires the iothread mutex, but is
also called for the EVTCHNOP_reset hypercall. Ensure the mutex is taken
in that case.

Fixes: a15b10978fe6 ("hw/xen: Implement EVTCHNOP_reset")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---
 hw/i386/kvm/xen_evtchn.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/i386/kvm/xen_evtchn.c b/hw/i386/kvm/xen_evtchn.c
index 3d6f4b4a0a..b2b4be9983 100644
--- a/hw/i386/kvm/xen_evtchn.c
+++ b/hw/i386/kvm/xen_evtchn.c
@@ -1135,6 +1135,7 @@ int xen_evtchn_reset_op(struct evtchn_reset *reset)
         return -ESRCH;
     }
 
+    QEMU_IOTHREAD_LOCK_GUARD();
     return xen_evtchn_soft_reset();
 }
 
-- 
2.40.1

Re: [PATCH v3 06/28] hw/xen: take iothread mutex in xen_evtchn_reset_op()

Posted by Durrant, Paul 2 years, 3 months ago

On 25/10/2023 15:50, David Woodhouse wrote:
> From: David Woodhouse <dwmw@amazon.co.uk>
> 
> The xen_evtchn_soft_reset() function requires the iothread mutex, but is
> also called for the EVTCHNOP_reset hypercall. Ensure the mutex is taken
> in that case.
> 
> Fixes: a15b10978fe6 ("hw/xen: Implement EVTCHNOP_reset")
> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
> ---
>   hw/i386/kvm/xen_evtchn.c | 1 +
>   1 file changed, 1 insertion(+)
> 

Reviewed-by: Paul Durrant <paul@xen.org>